The appeal comes just as the Privy Council, made up of politicians and other senior advisers, is due to take the final step towards imposing a new set of Press rules which was written by politicians and media campaigners.

Ministers hope the Privy Council meeting, chaired by Nick Clegg, the Deputy Prime Minister, will end debate over Press regulation following last year’s inquiry by Lord Justice Leveson into wrongdoing by tabloid journalists.

The Government’s plan for statutory regulation has been strongly criticised by the newspaper industry and by civil liberties campaigners, who say the prospect of politicians forcing their own rules on journalists poses a threat to free speech.

Richard Gordon QC, for the Press Standards Board of Finance (PressBof), told the High Court: “This was in all but name an executive roller-coasting through a charter which was one that the Government saw perhaps as the best way of implementing the Leveson recommendations.”

He said it was impossible for the public interest to be served by “rushing through” a charter.

“The public interest in this unique case lies in the fact that what is envisaged in the Government charter is the possibility of executive control of the Press for the first time since 1695,” said Mr Gordon.

“The concern of the claimants in the application for judicial review that has been lodged is that the Press charter has simply not been considered fairly.

“We would add to that, it has not been considered rationally, and we would add to that, it has not been considered lawfully.”

Mr Gordon suggested that the Government had behaved in a “Kafka-esque” way in keeping the publishers in the dark about what was happening until October 8, when a Privy Council committee composed of ministers and other political figures rejected the industry’s proposed Royal Charter.

Nathalie Lieven QC, for the government, said it would be “constitutionally improper” to grant PressBof’s applications and described the case as "unprecedented".

“In substance this ... is an attempt to re-argue issues that were considered at great length by Sir Brian Leveson,” she said.

Lord Justice Richards, sitting with Mr Justice Sales, said the merits of the publishers’ legal case were “at best weak”.

They refused an application for an injunction to delay the Privy Council’s decision.

The judges also rejected a separate application for a judicial review of the Privy Council’s earlier rejection of the newspaper industry’s plan for a regulator.

Lord Justice Richards said there was a strong public interest in allowing the Privy Council to proceed to consider the Government’s proposed charter, for which there was cross-party support and which had been endorsed by Parliament.

PressBof, the industry body which funds the regulatory system, is now expected to make an urgent appeal to the Court of Appeal, in a bid to beat the 5.30pm deadline when the Privy Council is due to meet.